2025-07-07 00:00:00 DStretch is a program for the PC and Mac that is used by rock art researchers to make faint rock art visible. This is a version for Android intended to be used in the field at a rock art site. Eight enhancements are provided together with settings that can adjust strength and saturation of the enhancements. Enhancements can be applied to a photo from the camera or from the gallery. The enhancements can be saved. For ease of use you can designate a default enhancement (I recommend CRGB) that is automatically applied when an image is loaded. The enhancements are: CRGB, YRD, YRE, RGB0: good for red pigments. YDT, YRD, YWE: general purpose. YDT, YBK, YYE: good for yellows.